Flipper Arms

Short of a better word to call them, that’s what I’ve named this part. They get attached to the linkage that attaches to the solenoid armature and do the actual turning of the flipper. I milled them out tonight, then found the length of the linkage part I need, 0.660″ on 1/8″ centered holes. I also need a longer M6 bolt, 30-35mm instead of the 25 that I have.

Anyway, the small hole is for a 3/32″ coiled spring pin to hold things together.

A Great Fit

So last night I cut a 3/8″ aluminum rod, drilled a hole through it, and tapped it for an M3 bolt. I had to ream the flipper’s 0.376″ hole out again, but once I did the rod fit perfectly. I screwed in the bolt and it looks great. Next step is to face the top of that flipper so I can put some rubber on it!IMG_20170518_183354

Parting the Parts

Last night I didn’t spend much time working, but I tested my drilling and counterboring techniques (still have room for improvement, but getting better) and parting the finished parts from the stock they were milled on. The final step in this process will be to face the top in the mill so it’s true to the bottom edge. My next steps are to mill the armature piece that turns the rod in the flipper, and to finish and test my complete flipper mechanism. So here are a couple of pictures of the parts removed from the stock. I really like the idea of leaving a shoulder around the part where I intend to cut it off, it made a great guide when I took it to the bandsaw, and even left a small bit of material so I’m not having to face down into the part and remove some of the height.

Sixth Time’s the Charm

I finally made a good flipper! After yesterday’s mistakes, I had three bits of raw material left to make the flippers I need. Today I examined my CNC programming, learned what mistakes I made and how to fix them (and hopefully avoid them in the future), and reprogrammed the mill to make my flipper. So I run through the whole process, three different tools, and it looks great. Then I put it next to yesterday’s failures and see that the 0.376″ hole looks way bigger than in should. Sure enough, the auto toolpath algorithm cut to the outside of the hole instead of the inside! So I get back to the CAM station (it’s connected to the milling machine), fix the toolpath, and go back and happily start getting my second flipper. Except when it gets to the hole, it’s cut too big again. Arg! Then I realize that although I fixed the toolpath, I never sent the revised instruction set to the milling machine and I just reran the bad program. *Sigh*

So I resend the file, cross my fingers, put my last bit of material in the vise, and start machining. Sure enough, I get my first viable part! Aside from my time, manufacturing this single flipper has cost me about $24 in materials. My next one, as long as I don’t make some other silly mistake, will cost me about $3. Way more reasonable.

I ended the night on a success, which is nice. Soon I’ll mill the other armature piece I need, and I’ll assemble the full flipper mechanism and be ready to test it!

Milling Prep

I had only a short time today, but I used it to get a refresher on the use of the software that runs the milling machine and to get the two new parts I’m milling ready to go. After some great suggestions from my mentor Marty, I decided to change the way I’m making the flipper and mill it upside down. It will take longer, but will allow me to accurately mill the 0.376″ hole in the bottom. It does mean using a key cutter to cut part of the outside profile though, since there is a 0.100″ overhang when cutting this way. The part will then be removed with a band saw and faced on the mill.

The second part, the arm that turns the flipper shaft, will be quicker to make but generally be done in the same fashion. I will be making these parts Monday evening after work.